Change a / 256 into a >> 8.

Originally committed as revision 23718 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/vp56.h

@@ -192,7 +192,7 @@ static inline void vp56_init_range_decoder(VP56RangeCoder *c,
 
 static inline int vp56_rac_get_prob(VP56RangeCoder *c, uint8_t prob)
 {
-    unsigned int low = 1 + (((c->high - 1) * prob) / 256);
+    unsigned int low = 1 + (((c->high - 1) * prob) >> 8);
     unsigned int low_shift = low << 8;
     int bit = c->code_word >= low_shift;